Lençóis Maranhenses National Park is a protected area on Brazil’s north Atlantic coast.
It’s known for its vast desert landscape of tall, white sand dunes and seasonal rainwater lagoons.
The name means “bedsheets” in Portuguese because of the spectacular landscape that is created by miles of rolling, smooth clean sand dunes.
It is far lesser-known – and visited – than Brazil’s other big natural wonder, Iguaçú falls, yet it is in many ways more dramatic and extraordinary.
While much of the park has the appearance of a desert, the area receives about 1,200 millimetres (47 in) of rain per year, while deserts, by definition, receive less than 250 millimetres (10 in) annually.
About 70% of this rainfall occurs between the months of January and May.
The sand is carried to the park from the interior of the continent by the Parnaíba and Preguiças rivers, where it is then driven back inland up to 50 kilometres by winds, creating a series of sand dunes rising as much as 130 ft tall.
During the rainy season, between the months of January and June, the rainstorms fill the spaces among the dunes with freshwater lagoons and together comprising as much as 41% of the area of the park.
The water in the lagoons is prevented from draining by a layer of impermeable rock located beneath the sandy surface.
The lagoons typically have a temperature between 27.5 °C (81.5 °F) and 32 °C (90 °F), pH of between 4.9 and 6.2, and low levels of dissolved nutrients.
When the dry season returns, the pools quickly evaporate, losing as much as 1 metre (3 ft) of depth per month.
The best way to reach the park is to get to São Luís, a former colonial city about four hours from Lençois Maranhenses. Flights from all over the county land regularly and once in the city, almost every pousada, hotel, or hostel will be able to arrange a transfer for you. Buses do the rounds picking up tourists from their accommodation around 7am each morning.
The park itself encompasses 70km of the coast, stretching 50km inland.
There are three main points of entry. Barreirinhas is the most sophisticated, having sprung up to cater to the visitors that flock to Lençois.
The town has a decent selection of all standards of accommodation, and from here it is easy to organise almost every kind of tour into the park, also, it is on the Rio Preguicas, a river named after sloths, which is good for paddle-boarding, kayaking and exploring the mangrove swamps.
There is a good selection of (mostly Brazilian) restaurants and a few bars.
Both Santo Amaro and Atins, which are on opposite sides of the park from each other are far less developed, more simple, and rather quiet.
The easiest (and cheapest) way to visit the park is to join a tour. Specially adapted trucks carry passengers on the back under a canopy, leaving with groups of up to ten each morning and evening. They take pre-arranged routes, usually stopping by the fullest lakes at that time of year and often including a meal at restaurants on the way into the park.
For more adventure, you can hire horses or quad bikes and set out with a guide to go where you please.
For all its beauty the park is a pretty harsh environment. The best time to go is between June and September when the lakes are full and plentiful and the sun is less intense.
By October the wind has picked up and there are far fewer lakes to visit.
